Scaring your clients may not be the best way to drum up new business, but that didn't stop Credit Suisse trying to strike terror into the hearts and minds of attendees on the opening day of its 2009 Asian investment conference.

In a telling sign of the times, the Swiss bank opted to entertain its clients yesterday evening not with a lavish cocktail party or expensive celebrity singers but with a screening of the 2008 financial horror film I.O.U.S.A.

If you've never heard of this chilling documentary, it's hardly surprising. Although it was billed as doing for the US economy what Al Gore's 2006 movie An Inconvenient Truth did for environmental awareness, the film faces a severe uphill struggle. The American people just don't want to know the bad news.

This soon becomes all too apparent. The film focuses on a campaign called The Fiscal Wake-Up Tour, in which former head of the US Government Accountability Office David Walker and other activists take an extended road trip across America in a Paul Revere-like attempt to alert the public to the dangers of fiscal irresponsibility.

The difficulty of their mission is illustrated - hilariously at times - by the film's vox pop interviews with ordinary Americans. Invariably, questions such as 'How big is the government's budget deficit?' or 'What is a trade deficit?' are met either with blank stares or wildly inaccurate replies like 'A couple of million?' or 'Is that when you borrow more than you spend?'.

It's not only the public who don't care. When the road show reaches New Hampshire, a report on ballooning US national debt levels by a diligent local television reporter is dropped from the evening news in favour of a story about a jewel thief who swallowed a stolen diamond ring in a bid to evade arrest.

Even sadder are the attempts by members of the Concerned Youth of America movement to spread their message on campus by handing out leaflets warning of the threat posed by the swelling US budget deficit. Their efforts are studiously ignored, and the remark by one campaigner that they are getting a good response appears not so much optimistic as desperately deluded.

Yet as the film makes clear in a series of interviews with the great and good of the US economy, from former treasury secretary Robert Rubin through ex-Federal Reserve chief Alan Greenspan to billionaire investor Warren Buffett, the dangers are real.

As one campaigner puts it, the root of the budget problem is America's addiction to 'big government spending and small government tax', which has seen the US national debt swell to about US$11 trillion, or more than two-thirds of gross domestic product.

But the truly scary thing is not the current debt level but its forecast future growth. As the first chart below shows, US spending on social security and health care is set to balloon over the coming years as the baby boom generation reaches retirement, pushing gross national debt to a projected 244 per cent of GDP by 2040.

As former head of the Congressional Budget Office Douglas Holtz-Eakin said in his introduction to last night's screening: 'Sadly, this is a documentary of the good old days when America had its fiscal house in order.'